I don't know if he'd see the value in it to him, I'd focus on basics.... but putting up a basic field fence would not be all that expensive and ecurbh and I know how to do it. It can be done if phases too... first the two sides that are exposed to the store and road, and then later the rest. Field fence is $100 or so for 330 feet.. just add posts and a gate.
That wouldn't be too bad, then! Would you just use that wire stuff that comes in rolls? Rabbit wire type stuff? Like I used for the dogs? I can't remember if I ever posted pictures of it. We didn't exactly do a great job, but it wasn't horribly expensive, I don't think.